Systemic Modulation of Gene Expression in Tomato by Trichoderma hamatum 382

Abstract

A light sphagnum peat mix inoculated with Trichoderma hamatum 382 consistently provided a significant (P = 0.05) degree of protection against bacterial spot of tomato and its pathogen Xanthomonas euvesicatoria 110c compared with the control peat mix, even though this biocontrol agent did not colonize aboveground plant parts. To gain insight into the mechanism by which T. hamatum 382 induced resistance in tomato, high-density oligonucleotide microarrays were used to determine its effect on the expression pattern of 15,925 genes in leaves just before they were inoculated with the pathogen. T. hamatum 382 consistently modulated the expression of genes in tomato leaves. We identified 45 genes to be differentially expressed across the replicated treatments, and 41 of these genes could be assigned to at least one of seven functional categories. T. hamatum 382-induced genes have functions associated with biotic or abiotic stress, as well as RNA, DNA, and protein metabolism. Four extensin and extensin-like proteins were induced. However, besides pathogenesis-related protein 5, the main markers of systemic acquired resistance were not significantly induced. This work showed that T. hamatum 382 actively induces systemic changes in plant physiology and disease resistance through systemic modulation of the expression of stress and metabolism genes.

Trichoderma gamsii affected herbivore feeding behaviour on Arabidopsis thaliana by modifying the leaf metabolome and phytohormones

“…In the Trichoderma ‐plant interaction, it has been shown that the fungus re‐programmes the plant's transcriptome, proteome and metabolome leading to enhancement of the plant's ability to tolerate different types of stresses (Alfano et al ., 2007; Shoresh et al ., 2010). …”

Comparative study of Trichoderma gene expression in interactions with tomato plants using high-density oligonucleotide microarrays

“…(Carpenter et al, 2005;Liu & Yang, 2005;Scherm et al, 2009;Vizcaíno et al, 2006Vizcaíno et al, , 2007. Several researchers have explored the responses of plants to the presence of a root-colonizing Trichoderma strain (Alfano et al, 2007;Marra et al, 2006;Segarra et al, 2007;Shoresh & Harman, 2008), but the fungal component of this association has been less studied. Macroarray analyses have been applied to study the gene expression of four species of Trichoderma during their interaction with cacao seedlings (Bailey et al, 2006), and of Trichoderma harzianum during the early colonization of tomato roots (Chacó n et al, 2007), although one limitation to such studies has been the low number of genes tested.…”

Biodiversity of Trichoderma in Neotropics

“…Many species of Trichoderma are closely associated with plant roots and specific strains may form endophytic associations with their plant host (Bailey et al, 2006, Evans et al, 2003, Hoyos-Carvajal et al, 2009bManesh et al, 2006, Sette et al, 2006, Viterbo & Chet 2006, Yedidia et al, 2000. As endophytes they are particularly effective biological control agents of fungi in the rhizosphere, producing antimicrobials, activating plant defence mechanisms, and stimulating plant growth and vigour by solubilizing minerals and providing other nutrients and growth regulating compounds (Alfano et al, 2007;Altomare et al 1999;Sharon et al, 2001;Vinale et al, 2006, Woo et al, 2006, Yedidia et al, 2000. The multiple roles of Trichoderma in biotrophic decomposition, parasitism and endophytic associations are of particular importance to the sustainability of agricultural and natural ecosystems (Harman et al 2004).…”